$ sudo apt-get install grub-legacy-ec2
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
  grub-legacy-doc
The following NEW packages will be installed:
  grub-legacy-ec2
0 upgraded, 1 newly installed, 0 to remove and 2 not upgraded.
1 not fully installed or removed.
Need to get 19,4 kB of archives.
After this operation, 82,9 kB of additional disk space will be used.
Get:1 http://ua.archive.ubuntu.com/ubuntu bionic/main amd64 grub-legacy-ec2 all 1:1 [19,4 kB]
Fetched 19,4 kB in 0s (42,5 kB/s)
Preconfiguring packages ...
(Reading database ... 111010 files and directories currently installed.)
Preparing to unpack .../grub-legacy-ec2_1%3a1_all.deb ...
Adding 'diversion of /usr/sbin/grub-set-default to /usr/sbin/grub-set-default.real by grub-legacy-ec2'
dpkg-divert: error: rename involves overwriting '/usr/sbin/grub-set-default.real' with
  different file '/usr/sbin/grub-set-default', not allowed
dpkg: error processing archive /var/cache/apt/archives/grub-legacy-ec2_1%3a1_all.deb (--unpack):
 new grub-legacy-ec2 package pre-installation script subprocess returned error exit status 2
Errors were encountered while processing:
 /var/cache/apt/archives/grub-legacy-ec2_1%3a1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)